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v4.17
   1/*
   2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
   3 *		operating system.  INET is implemented using the  BSD Socket
   4 *		interface as the means of communication with the user level.
   5 *
   6 *		"Ping" sockets
   7 *
   8 *		This program is free software; you can redistribute it and/or
   9 *		modify it under the terms of the GNU General Public License
  10 *		as published by the Free Software Foundation; either version
  11 *		2 of the License, or (at your option) any later version.
  12 *
  13 * Based on ipv4/udp.c code.
  14 *
  15 * Authors:	Vasiliy Kulikov / Openwall (for Linux 2.6),
  16 *		Pavel Kankovsky (for Linux 2.4.32)
  17 *
  18 * Pavel gave all rights to bugs to Vasiliy,
  19 * none of the bugs are Pavel's now.
  20 *
  21 */
  22
  23#include <linux/uaccess.h>
  24#include <linux/types.h>
  25#include <linux/fcntl.h>
  26#include <linux/socket.h>
  27#include <linux/sockios.h>
  28#include <linux/in.h>
  29#include <linux/errno.h>
  30#include <linux/timer.h>
  31#include <linux/mm.h>
  32#include <linux/inet.h>
  33#include <linux/netdevice.h>
  34#include <net/snmp.h>
  35#include <net/ip.h>
  36#include <net/icmp.h>
  37#include <net/protocol.h>
  38#include <linux/skbuff.h>
  39#include <linux/proc_fs.h>
  40#include <linux/export.h>
  41#include <net/sock.h>
  42#include <net/ping.h>
  43#include <net/udp.h>
  44#include <net/route.h>
  45#include <net/inet_common.h>
  46#include <net/checksum.h>
  47
  48#if IS_ENABLED(CONFIG_IPV6)
  49#include <linux/in6.h>
  50#include <linux/icmpv6.h>
  51#include <net/addrconf.h>
  52#include <net/ipv6.h>
  53#include <net/transp_v6.h>
  54#endif
  55
  56struct ping_table {
  57	struct hlist_nulls_head	hash[PING_HTABLE_SIZE];
  58	rwlock_t		lock;
  59};
  60
  61static struct ping_table ping_table;
  62struct pingv6_ops pingv6_ops;
  63EXPORT_SYMBOL_GPL(pingv6_ops);
  64
  65static u16 ping_port_rover;
  66
  67static inline u32 ping_hashfn(const struct net *net, u32 num, u32 mask)
  68{
  69	u32 res = (num + net_hash_mix(net)) & mask;
  70
  71	pr_debug("hash(%u) = %u\n", num, res);
  72	return res;
  73}
  74EXPORT_SYMBOL_GPL(ping_hash);
  75
  76static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
  77					     struct net *net, unsigned int num)
  78{
  79	return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
  80}
  81
  82int ping_get_port(struct sock *sk, unsigned short ident)
  83{
  84	struct hlist_nulls_node *node;
  85	struct hlist_nulls_head *hlist;
  86	struct inet_sock *isk, *isk2;
  87	struct sock *sk2 = NULL;
  88
  89	isk = inet_sk(sk);
  90	write_lock_bh(&ping_table.lock);
  91	if (ident == 0) {
  92		u32 i;
  93		u16 result = ping_port_rover + 1;
  94
  95		for (i = 0; i < (1L << 16); i++, result++) {
  96			if (!result)
  97				result++; /* avoid zero */
  98			hlist = ping_hashslot(&ping_table, sock_net(sk),
  99					    result);
 100			ping_portaddr_for_each_entry(sk2, node, hlist) {
 101				isk2 = inet_sk(sk2);
 102
 103				if (isk2->inet_num == result)
 104					goto next_port;
 105			}
 106
 107			/* found */
 108			ping_port_rover = ident = result;
 109			break;
 110next_port:
 111			;
 112		}
 113		if (i >= (1L << 16))
 114			goto fail;
 115	} else {
 116		hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
 117		ping_portaddr_for_each_entry(sk2, node, hlist) {
 118			isk2 = inet_sk(sk2);
 119
 120			/* BUG? Why is this reuse and not reuseaddr? ping.c
 121			 * doesn't turn off SO_REUSEADDR, and it doesn't expect
 122			 * that other ping processes can steal its packets.
 123			 */
 124			if ((isk2->inet_num == ident) &&
 125			    (sk2 != sk) &&
 126			    (!sk2->sk_reuse || !sk->sk_reuse))
 127				goto fail;
 128		}
 129	}
 130
 131	pr_debug("found port/ident = %d\n", ident);
 132	isk->inet_num = ident;
 133	if (sk_unhashed(sk)) {
 134		pr_debug("was not hashed\n");
 135		sock_hold(sk);
 136		hlist_nulls_add_head(&sk->sk_nulls_node, hlist);
 137		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 138	}
 139	write_unlock_bh(&ping_table.lock);
 140	return 0;
 141
 142fail:
 143	write_unlock_bh(&ping_table.lock);
 144	return 1;
 145}
 146EXPORT_SYMBOL_GPL(ping_get_port);
 147
 148int ping_hash(struct sock *sk)
 149{
 150	pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
 151	BUG(); /* "Please do not press this button again." */
 152
 153	return 0;
 154}
 155
 156void ping_unhash(struct sock *sk)
 157{
 158	struct inet_sock *isk = inet_sk(sk);
 159
 160	pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
 161	write_lock_bh(&ping_table.lock);
 162	if (sk_hashed(sk)) {
 
 163		hlist_nulls_del(&sk->sk_nulls_node);
 164		sk_nulls_node_init(&sk->sk_nulls_node);
 165		sock_put(sk);
 166		isk->inet_num = 0;
 167		isk->inet_sport = 0;
 168		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 
 169	}
 170	write_unlock_bh(&ping_table.lock);
 171}
 172EXPORT_SYMBOL_GPL(ping_unhash);
 173
 174static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
 175{
 176	struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
 177	struct sock *sk = NULL;
 178	struct inet_sock *isk;
 179	struct hlist_nulls_node *hnode;
 180	int dif = skb->dev->ifindex;
 181
 182	if (skb->protocol == htons(ETH_P_IP)) {
 183		pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
 184			 (int)ident, &ip_hdr(skb)->daddr, dif);
 185#if IS_ENABLED(CONFIG_IPV6)
 186	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 187		pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n",
 188			 (int)ident, &ipv6_hdr(skb)->daddr, dif);
 189#endif
 190	}
 191
 192	read_lock_bh(&ping_table.lock);
 193
 194	ping_portaddr_for_each_entry(sk, hnode, hslot) {
 195		isk = inet_sk(sk);
 196
 197		pr_debug("iterate\n");
 198		if (isk->inet_num != ident)
 199			continue;
 200
 201		if (skb->protocol == htons(ETH_P_IP) &&
 202		    sk->sk_family == AF_INET) {
 203			pr_debug("found: %p: num=%d, daddr=%pI4, dif=%d\n", sk,
 204				 (int) isk->inet_num, &isk->inet_rcv_saddr,
 205				 sk->sk_bound_dev_if);
 206
 207			if (isk->inet_rcv_saddr &&
 208			    isk->inet_rcv_saddr != ip_hdr(skb)->daddr)
 209				continue;
 210#if IS_ENABLED(CONFIG_IPV6)
 211		} else if (skb->protocol == htons(ETH_P_IPV6) &&
 212			   sk->sk_family == AF_INET6) {
 213
 214			pr_debug("found: %p: num=%d, daddr=%pI6c, dif=%d\n", sk,
 215				 (int) isk->inet_num,
 216				 &sk->sk_v6_rcv_saddr,
 217				 sk->sk_bound_dev_if);
 218
 219			if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
 220			    !ipv6_addr_equal(&sk->sk_v6_rcv_saddr,
 221					     &ipv6_hdr(skb)->daddr))
 222				continue;
 223#endif
 224		} else {
 225			continue;
 226		}
 227
 228		if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)
 229			continue;
 230
 231		sock_hold(sk);
 232		goto exit;
 233	}
 234
 235	sk = NULL;
 236exit:
 237	read_unlock_bh(&ping_table.lock);
 238
 239	return sk;
 240}
 241
 242static void inet_get_ping_group_range_net(struct net *net, kgid_t *low,
 243					  kgid_t *high)
 244{
 245	kgid_t *data = net->ipv4.ping_group_range.range;
 246	unsigned int seq;
 247
 248	do {
 249		seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
 250
 251		*low = data[0];
 252		*high = data[1];
 253	} while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
 254}
 255
 256
 257int ping_init_sock(struct sock *sk)
 258{
 259	struct net *net = sock_net(sk);
 260	kgid_t group = current_egid();
 261	struct group_info *group_info;
 262	int i;
 263	kgid_t low, high;
 264	int ret = 0;
 265
 266	if (sk->sk_family == AF_INET6)
 267		sk->sk_ipv6only = 1;
 268
 269	inet_get_ping_group_range_net(net, &low, &high);
 270	if (gid_lte(low, group) && gid_lte(group, high))
 271		return 0;
 272
 273	group_info = get_current_groups();
 274	for (i = 0; i < group_info->ngroups; i++) {
 275		kgid_t gid = group_info->gid[i];
 
 
 
 
 
 
 276
 277		if (gid_lte(low, gid) && gid_lte(gid, high))
 278			goto out_release_group;
 279	}
 280
 281	ret = -EACCES;
 282
 283out_release_group:
 284	put_group_info(group_info);
 285	return ret;
 286}
 287EXPORT_SYMBOL_GPL(ping_init_sock);
 288
 289void ping_close(struct sock *sk, long timeout)
 290{
 291	pr_debug("ping_close(sk=%p,sk->num=%u)\n",
 292		 inet_sk(sk), inet_sk(sk)->inet_num);
 293	pr_debug("isk->refcnt = %d\n", refcount_read(&sk->sk_refcnt));
 294
 295	sk_common_release(sk);
 296}
 297EXPORT_SYMBOL_GPL(ping_close);
 298
 299/* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
 300static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk,
 301				struct sockaddr *uaddr, int addr_len) {
 302	struct net *net = sock_net(sk);
 303	if (sk->sk_family == AF_INET) {
 304		struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
 305		int chk_addr_ret;
 306
 307		if (addr_len < sizeof(*addr))
 308			return -EINVAL;
 309
 310		if (addr->sin_family != AF_INET &&
 311		    !(addr->sin_family == AF_UNSPEC &&
 312		      addr->sin_addr.s_addr == htonl(INADDR_ANY)))
 313			return -EAFNOSUPPORT;
 314
 315		pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
 316			 sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
 317
 318		chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr);
 319
 320		if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
 321			chk_addr_ret = RTN_LOCAL;
 322
 323		if ((net->ipv4.sysctl_ip_nonlocal_bind == 0 &&
 324		    isk->freebind == 0 && isk->transparent == 0 &&
 325		     chk_addr_ret != RTN_LOCAL) ||
 326		    chk_addr_ret == RTN_MULTICAST ||
 327		    chk_addr_ret == RTN_BROADCAST)
 328			return -EADDRNOTAVAIL;
 329
 330#if IS_ENABLED(CONFIG_IPV6)
 331	} else if (sk->sk_family == AF_INET6) {
 332		struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
 333		int addr_type, scoped, has_addr;
 334		struct net_device *dev = NULL;
 335
 336		if (addr_len < sizeof(*addr))
 337			return -EINVAL;
 338
 339		if (addr->sin6_family != AF_INET6)
 340			return -EAFNOSUPPORT;
 341
 342		pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
 343			 sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
 344
 345		addr_type = ipv6_addr_type(&addr->sin6_addr);
 346		scoped = __ipv6_addr_needs_scope_id(addr_type);
 347		if ((addr_type != IPV6_ADDR_ANY &&
 348		     !(addr_type & IPV6_ADDR_UNICAST)) ||
 349		    (scoped && !addr->sin6_scope_id))
 350			return -EINVAL;
 351
 352		rcu_read_lock();
 353		if (addr->sin6_scope_id) {
 354			dev = dev_get_by_index_rcu(net, addr->sin6_scope_id);
 355			if (!dev) {
 356				rcu_read_unlock();
 357				return -ENODEV;
 358			}
 359		}
 360		has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,
 361						    scoped);
 362		rcu_read_unlock();
 363
 364		if (!(net->ipv6.sysctl.ip_nonlocal_bind ||
 365		      isk->freebind || isk->transparent || has_addr ||
 366		      addr_type == IPV6_ADDR_ANY))
 367			return -EADDRNOTAVAIL;
 368
 369		if (scoped)
 370			sk->sk_bound_dev_if = addr->sin6_scope_id;
 371#endif
 372	} else {
 373		return -EAFNOSUPPORT;
 374	}
 375	return 0;
 376}
 377
 378static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr)
 379{
 380	if (saddr->sa_family == AF_INET) {
 381		struct inet_sock *isk = inet_sk(sk);
 382		struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
 383		isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
 384#if IS_ENABLED(CONFIG_IPV6)
 385	} else if (saddr->sa_family == AF_INET6) {
 386		struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
 387		struct ipv6_pinfo *np = inet6_sk(sk);
 388		sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr;
 389#endif
 390	}
 391}
 392
 393static void ping_clear_saddr(struct sock *sk, int dif)
 394{
 395	sk->sk_bound_dev_if = dif;
 396	if (sk->sk_family == AF_INET) {
 397		struct inet_sock *isk = inet_sk(sk);
 398		isk->inet_rcv_saddr = isk->inet_saddr = 0;
 399#if IS_ENABLED(CONFIG_IPV6)
 400	} else if (sk->sk_family == AF_INET6) {
 401		struct ipv6_pinfo *np = inet6_sk(sk);
 402		memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
 403		memset(&np->saddr, 0, sizeof(np->saddr));
 404#endif
 405	}
 406}
 407/*
 408 * We need our own bind because there are no privileged id's == local ports.
 409 * Moreover, we don't allow binding to multi- and broadcast addresses.
 410 */
 411
 412int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 413{
 414	struct inet_sock *isk = inet_sk(sk);
 415	unsigned short snum;
 416	int err;
 417	int dif = sk->sk_bound_dev_if;
 418
 419	err = ping_check_bind_addr(sk, isk, uaddr, addr_len);
 420	if (err)
 421		return err;
 422
 423	lock_sock(sk);
 424
 425	err = -EINVAL;
 426	if (isk->inet_num != 0)
 427		goto out;
 428
 429	err = -EADDRINUSE;
 430	ping_set_saddr(sk, uaddr);
 431	snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port);
 432	if (ping_get_port(sk, snum) != 0) {
 433		ping_clear_saddr(sk, dif);
 434		goto out;
 435	}
 436
 437	pr_debug("after bind(): num = %hu, dif = %d\n",
 438		 isk->inet_num,
 439		 sk->sk_bound_dev_if);
 440
 441	err = 0;
 442	if (sk->sk_family == AF_INET && isk->inet_rcv_saddr)
 443		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 444#if IS_ENABLED(CONFIG_IPV6)
 445	if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr))
 446		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 447#endif
 448
 449	if (snum)
 450		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 451	isk->inet_sport = htons(isk->inet_num);
 452	isk->inet_daddr = 0;
 453	isk->inet_dport = 0;
 454
 455#if IS_ENABLED(CONFIG_IPV6)
 456	if (sk->sk_family == AF_INET6)
 457		memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
 458#endif
 459
 460	sk_dst_reset(sk);
 461out:
 462	release_sock(sk);
 463	pr_debug("ping_v4_bind -> %d\n", err);
 464	return err;
 465}
 466EXPORT_SYMBOL_GPL(ping_bind);
 467
 468/*
 469 * Is this a supported type of ICMP message?
 470 */
 471
 472static inline int ping_supported(int family, int type, int code)
 473{
 474	return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
 475	       (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0);
 476}
 477
 478/*
 479 * This routine is called by the ICMP module when it gets some
 480 * sort of error condition.
 481 */
 482
 483void ping_err(struct sk_buff *skb, int offset, u32 info)
 484{
 485	int family;
 486	struct icmphdr *icmph;
 487	struct inet_sock *inet_sock;
 488	int type;
 489	int code;
 490	struct net *net = dev_net(skb->dev);
 491	struct sock *sk;
 492	int harderr;
 493	int err;
 494
 495	if (skb->protocol == htons(ETH_P_IP)) {
 496		family = AF_INET;
 497		type = icmp_hdr(skb)->type;
 498		code = icmp_hdr(skb)->code;
 499		icmph = (struct icmphdr *)(skb->data + offset);
 500	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 501		family = AF_INET6;
 502		type = icmp6_hdr(skb)->icmp6_type;
 503		code = icmp6_hdr(skb)->icmp6_code;
 504		icmph = (struct icmphdr *) (skb->data + offset);
 505	} else {
 506		BUG();
 507	}
 508
 509	/* We assume the packet has already been checked by icmp_unreach */
 510
 511	if (!ping_supported(family, icmph->type, icmph->code))
 512		return;
 513
 514	pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n",
 515		 skb->protocol, type, code, ntohs(icmph->un.echo.id),
 516		 ntohs(icmph->un.echo.sequence));
 517
 518	sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
 519	if (!sk) {
 520		pr_debug("no socket, dropping\n");
 521		return;	/* No socket for error */
 522	}
 523	pr_debug("err on socket %p\n", sk);
 524
 525	err = 0;
 526	harderr = 0;
 527	inet_sock = inet_sk(sk);
 528
 529	if (skb->protocol == htons(ETH_P_IP)) {
 530		switch (type) {
 531		default:
 532		case ICMP_TIME_EXCEEDED:
 533			err = EHOSTUNREACH;
 534			break;
 535		case ICMP_SOURCE_QUENCH:
 536			/* This is not a real error but ping wants to see it.
 537			 * Report it with some fake errno.
 538			 */
 539			err = EREMOTEIO;
 540			break;
 541		case ICMP_PARAMETERPROB:
 542			err = EPROTO;
 543			harderr = 1;
 544			break;
 545		case ICMP_DEST_UNREACH:
 546			if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
 547				ipv4_sk_update_pmtu(skb, sk, info);
 548				if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
 549					err = EMSGSIZE;
 550					harderr = 1;
 551					break;
 552				}
 553				goto out;
 554			}
 555			err = EHOSTUNREACH;
 556			if (code <= NR_ICMP_UNREACH) {
 557				harderr = icmp_err_convert[code].fatal;
 558				err = icmp_err_convert[code].errno;
 559			}
 560			break;
 561		case ICMP_REDIRECT:
 562			/* See ICMP_SOURCE_QUENCH */
 563			ipv4_sk_redirect(skb, sk);
 564			err = EREMOTEIO;
 565			break;
 566		}
 567#if IS_ENABLED(CONFIG_IPV6)
 568	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 569		harderr = pingv6_ops.icmpv6_err_convert(type, code, &err);
 570#endif
 571	}
 572
 573	/*
 574	 *      RFC1122: OK.  Passes ICMP errors back to application, as per
 575	 *	4.1.3.3.
 576	 */
 577	if ((family == AF_INET && !inet_sock->recverr) ||
 578	    (family == AF_INET6 && !inet6_sk(sk)->recverr)) {
 579		if (!harderr || sk->sk_state != TCP_ESTABLISHED)
 580			goto out;
 581	} else {
 582		if (family == AF_INET) {
 583			ip_icmp_error(sk, skb, err, 0 /* no remote port */,
 584				      info, (u8 *)icmph);
 585#if IS_ENABLED(CONFIG_IPV6)
 586		} else if (family == AF_INET6) {
 587			pingv6_ops.ipv6_icmp_error(sk, skb, err, 0,
 588						   info, (u8 *)icmph);
 589#endif
 590		}
 591	}
 592	sk->sk_err = err;
 593	sk->sk_error_report(sk);
 594out:
 595	sock_put(sk);
 596}
 597EXPORT_SYMBOL_GPL(ping_err);
 598
 599/*
 600 *	Copy and checksum an ICMP Echo packet from user space into a buffer
 601 *	starting from the payload.
 602 */
 603
 604int ping_getfrag(void *from, char *to,
 605		 int offset, int fraglen, int odd, struct sk_buff *skb)
 606{
 607	struct pingfakehdr *pfh = (struct pingfakehdr *)from;
 608
 609	if (offset == 0) {
 610		fraglen -= sizeof(struct icmphdr);
 611		if (fraglen < 0)
 612			BUG();
 613		if (!csum_and_copy_from_iter_full(to + sizeof(struct icmphdr),
 614			    fraglen, &pfh->wcheck,
 615			    &pfh->msg->msg_iter))
 616			return -EFAULT;
 617	} else if (offset < sizeof(struct icmphdr)) {
 618			BUG();
 619	} else {
 620		if (!csum_and_copy_from_iter_full(to, fraglen, &pfh->wcheck,
 621					    &pfh->msg->msg_iter))
 
 622			return -EFAULT;
 623	}
 624
 625#if IS_ENABLED(CONFIG_IPV6)
 626	/* For IPv6, checksum each skb as we go along, as expected by
 627	 * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in
 628	 * wcheck, it will be finalized in ping_v4_push_pending_frames.
 629	 */
 630	if (pfh->family == AF_INET6) {
 631		skb->csum = pfh->wcheck;
 632		skb->ip_summed = CHECKSUM_NONE;
 633		pfh->wcheck = 0;
 634	}
 635#endif
 636
 637	return 0;
 638}
 639EXPORT_SYMBOL_GPL(ping_getfrag);
 640
 641static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
 642				       struct flowi4 *fl4)
 643{
 644	struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
 645
 646	if (!skb)
 647		return 0;
 648	pfh->wcheck = csum_partial((char *)&pfh->icmph,
 649		sizeof(struct icmphdr), pfh->wcheck);
 650	pfh->icmph.checksum = csum_fold(pfh->wcheck);
 651	memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
 652	skb->ip_summed = CHECKSUM_NONE;
 653	return ip_push_pending_frames(sk, fl4);
 654}
 655
 656int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
 657			void *user_icmph, size_t icmph_len) {
 658	u8 type, code;
 659
 660	if (len > 0xFFFF)
 661		return -EMSGSIZE;
 662
 663	/* Must have at least a full ICMP header. */
 664	if (len < icmph_len)
 665		return -EINVAL;
 666
 667	/*
 668	 *	Check the flags.
 669	 */
 670
 671	/* Mirror BSD error message compatibility */
 672	if (msg->msg_flags & MSG_OOB)
 673		return -EOPNOTSUPP;
 674
 675	/*
 676	 *	Fetch the ICMP header provided by the userland.
 677	 *	iovec is modified! The ICMP header is consumed.
 678	 */
 679	if (memcpy_from_msg(user_icmph, msg, icmph_len))
 680		return -EFAULT;
 681
 682	if (family == AF_INET) {
 683		type = ((struct icmphdr *) user_icmph)->type;
 684		code = ((struct icmphdr *) user_icmph)->code;
 685#if IS_ENABLED(CONFIG_IPV6)
 686	} else if (family == AF_INET6) {
 687		type = ((struct icmp6hdr *) user_icmph)->icmp6_type;
 688		code = ((struct icmp6hdr *) user_icmph)->icmp6_code;
 689#endif
 690	} else {
 691		BUG();
 692	}
 693
 694	if (!ping_supported(family, type, code))
 695		return -EINVAL;
 696
 697	return 0;
 698}
 699EXPORT_SYMBOL_GPL(ping_common_sendmsg);
 700
 701static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 
 702{
 703	struct net *net = sock_net(sk);
 704	struct flowi4 fl4;
 705	struct inet_sock *inet = inet_sk(sk);
 706	struct ipcm_cookie ipc;
 707	struct icmphdr user_icmph;
 708	struct pingfakehdr pfh;
 709	struct rtable *rt = NULL;
 710	struct ip_options_data opt_copy;
 711	int free = 0;
 712	__be32 saddr, daddr, faddr;
 713	u8  tos;
 714	int err;
 715
 716	pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
 717
 718	err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph,
 719				  sizeof(user_icmph));
 720	if (err)
 721		return err;
 722
 723	/*
 724	 *	Get and verify the address.
 725	 */
 726
 727	if (msg->msg_name) {
 728		DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
 729		if (msg->msg_namelen < sizeof(*usin))
 730			return -EINVAL;
 731		if (usin->sin_family != AF_INET)
 732			return -EAFNOSUPPORT;
 733		daddr = usin->sin_addr.s_addr;
 734		/* no remote port */
 735	} else {
 736		if (sk->sk_state != TCP_ESTABLISHED)
 737			return -EDESTADDRREQ;
 738		daddr = inet->inet_daddr;
 739		/* no remote port */
 740	}
 741
 742	ipc.sockc.tsflags = sk->sk_tsflags;
 743	ipc.addr = inet->inet_saddr;
 744	ipc.opt = NULL;
 745	ipc.oif = sk->sk_bound_dev_if;
 746	ipc.tx_flags = 0;
 747	ipc.ttl = 0;
 748	ipc.tos = -1;
 749
 
 
 750	if (msg->msg_controllen) {
 751		err = ip_cmsg_send(sk, msg, &ipc, false);
 752		if (unlikely(err)) {
 753			kfree(ipc.opt);
 754			return err;
 755		}
 756		if (ipc.opt)
 757			free = 1;
 758	}
 759	if (!ipc.opt) {
 760		struct ip_options_rcu *inet_opt;
 761
 762		rcu_read_lock();
 763		inet_opt = rcu_dereference(inet->inet_opt);
 764		if (inet_opt) {
 765			memcpy(&opt_copy, inet_opt,
 766			       sizeof(*inet_opt) + inet_opt->opt.optlen);
 767			ipc.opt = &opt_copy.opt;
 768		}
 769		rcu_read_unlock();
 770	}
 771
 772	sock_tx_timestamp(sk, ipc.sockc.tsflags, &ipc.tx_flags);
 773
 774	saddr = ipc.addr;
 775	ipc.addr = faddr = daddr;
 776
 777	if (ipc.opt && ipc.opt->opt.srr) {
 778		if (!daddr) {
 779			err = -EINVAL;
 780			goto out_free;
 781		}
 782		faddr = ipc.opt->opt.faddr;
 783	}
 784	tos = get_rttos(&ipc, inet);
 785	if (sock_flag(sk, SOCK_LOCALROUTE) ||
 786	    (msg->msg_flags & MSG_DONTROUTE) ||
 787	    (ipc.opt && ipc.opt->opt.is_strictroute)) {
 788		tos |= RTO_ONLINK;
 789	}
 790
 791	if (ipv4_is_multicast(daddr)) {
 792		if (!ipc.oif)
 793			ipc.oif = inet->mc_index;
 794		if (!saddr)
 795			saddr = inet->mc_addr;
 796	} else if (!ipc.oif)
 797		ipc.oif = inet->uc_index;
 798
 799	flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
 800			   RT_SCOPE_UNIVERSE, sk->sk_protocol,
 801			   inet_sk_flowi_flags(sk), faddr, saddr, 0, 0,
 802			   sk->sk_uid);
 803
 804	security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
 805	rt = ip_route_output_flow(net, &fl4, sk);
 806	if (IS_ERR(rt)) {
 807		err = PTR_ERR(rt);
 808		rt = NULL;
 809		if (err == -ENETUNREACH)
 810			IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
 811		goto out;
 812	}
 813
 814	err = -EACCES;
 815	if ((rt->rt_flags & RTCF_BROADCAST) &&
 816	    !sock_flag(sk, SOCK_BROADCAST))
 817		goto out;
 818
 819	if (msg->msg_flags & MSG_CONFIRM)
 820		goto do_confirm;
 821back_from_confirm:
 822
 823	if (!ipc.addr)
 824		ipc.addr = fl4.daddr;
 825
 826	lock_sock(sk);
 827
 828	pfh.icmph.type = user_icmph.type; /* already checked */
 829	pfh.icmph.code = user_icmph.code; /* ditto */
 830	pfh.icmph.checksum = 0;
 831	pfh.icmph.un.echo.id = inet->inet_sport;
 832	pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
 833	pfh.msg = msg;
 834	pfh.wcheck = 0;
 835	pfh.family = AF_INET;
 836
 837	err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
 838			0, &ipc, &rt, msg->msg_flags);
 839	if (err)
 840		ip_flush_pending_frames(sk);
 841	else
 842		err = ping_v4_push_pending_frames(sk, &pfh, &fl4);
 843	release_sock(sk);
 844
 845out:
 846	ip_rt_put(rt);
 847out_free:
 848	if (free)
 849		kfree(ipc.opt);
 850	if (!err) {
 851		icmp_out_count(sock_net(sk), user_icmph.type);
 852		return len;
 853	}
 854	return err;
 855
 856do_confirm:
 857	if (msg->msg_flags & MSG_PROBE)
 858		dst_confirm_neigh(&rt->dst, &fl4.daddr);
 859	if (!(msg->msg_flags & MSG_PROBE) || len)
 860		goto back_from_confirm;
 861	err = 0;
 862	goto out;
 863}
 864
 865int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
 866		 int flags, int *addr_len)
 867{
 868	struct inet_sock *isk = inet_sk(sk);
 869	int family = sk->sk_family;
 870	struct sk_buff *skb;
 871	int copied, err;
 872
 873	pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
 874
 875	err = -EOPNOTSUPP;
 876	if (flags & MSG_OOB)
 877		goto out;
 878
 879	if (flags & MSG_ERRQUEUE)
 880		return inet_recv_error(sk, msg, len, addr_len);
 
 
 
 
 
 
 
 
 881
 882	skb = skb_recv_datagram(sk, flags, noblock, &err);
 883	if (!skb)
 884		goto out;
 885
 886	copied = skb->len;
 887	if (copied > len) {
 888		msg->msg_flags |= MSG_TRUNC;
 889		copied = len;
 890	}
 891
 892	/* Don't bother checking the checksum */
 893	err = skb_copy_datagram_msg(skb, 0, msg, copied);
 894	if (err)
 895		goto done;
 896
 897	sock_recv_timestamp(msg, sk, skb);
 898
 899	/* Copy the address and add cmsg data. */
 900	if (family == AF_INET) {
 901		DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
 902
 903		if (sin) {
 904			sin->sin_family = AF_INET;
 905			sin->sin_port = 0 /* skb->h.uh->source */;
 906			sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
 907			memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 908			*addr_len = sizeof(*sin);
 909		}
 910
 911		if (isk->cmsg_flags)
 912			ip_cmsg_recv(msg, skb);
 913
 914#if IS_ENABLED(CONFIG_IPV6)
 915	} else if (family == AF_INET6) {
 916		struct ipv6_pinfo *np = inet6_sk(sk);
 917		struct ipv6hdr *ip6 = ipv6_hdr(skb);
 918		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
 919
 920		if (sin6) {
 921			sin6->sin6_family = AF_INET6;
 922			sin6->sin6_port = 0;
 923			sin6->sin6_addr = ip6->saddr;
 924			sin6->sin6_flowinfo = 0;
 925			if (np->sndflow)
 926				sin6->sin6_flowinfo = ip6_flowinfo(ip6);
 927			sin6->sin6_scope_id =
 928				ipv6_iface_scope_id(&sin6->sin6_addr,
 929						    inet6_iif(skb));
 930			*addr_len = sizeof(*sin6);
 931		}
 932
 933		if (inet6_sk(sk)->rxopt.all)
 934			pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb);
 935		if (skb->protocol == htons(ETH_P_IPV6) &&
 936		    inet6_sk(sk)->rxopt.all)
 937			pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb);
 938		else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags)
 939			ip_cmsg_recv(msg, skb);
 940#endif
 941	} else {
 942		BUG();
 943	}
 944
 945	err = copied;
 946
 947done:
 948	skb_free_datagram(sk, skb);
 949out:
 950	pr_debug("ping_recvmsg -> %d\n", err);
 951	return err;
 952}
 953EXPORT_SYMBOL_GPL(ping_recvmsg);
 954
 955int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 956{
 957	pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
 958		 inet_sk(sk), inet_sk(sk)->inet_num, skb);
 959	if (sock_queue_rcv_skb(sk, skb) < 0) {
 960		kfree_skb(skb);
 961		pr_debug("ping_queue_rcv_skb -> failed\n");
 962		return -1;
 963	}
 964	return 0;
 965}
 966EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
 967
 968
 969/*
 970 *	All we need to do is get the socket.
 971 */
 972
 973bool ping_rcv(struct sk_buff *skb)
 974{
 975	struct sock *sk;
 976	struct net *net = dev_net(skb->dev);
 977	struct icmphdr *icmph = icmp_hdr(skb);
 978
 979	/* We assume the packet has already been checked by icmp_rcv */
 980
 981	pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
 982		 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
 983
 984	/* Push ICMP header back */
 985	skb_push(skb, skb->data - (u8 *)icmph);
 986
 987	sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
 988	if (sk) {
 989		struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 990
 991		pr_debug("rcv on socket %p\n", sk);
 992		if (skb2)
 993			ping_queue_rcv_skb(sk, skb2);
 994		sock_put(sk);
 995		return true;
 996	}
 997	pr_debug("no socket, dropping\n");
 998
 999	return false;
1000}
1001EXPORT_SYMBOL_GPL(ping_rcv);
1002
1003struct proto ping_prot = {
1004	.name =		"PING",
1005	.owner =	THIS_MODULE,
1006	.init =		ping_init_sock,
1007	.close =	ping_close,
1008	.connect =	ip4_datagram_connect,
1009	.disconnect =	__udp_disconnect,
1010	.setsockopt =	ip_setsockopt,
1011	.getsockopt =	ip_getsockopt,
1012	.sendmsg =	ping_v4_sendmsg,
1013	.recvmsg =	ping_recvmsg,
1014	.bind =		ping_bind,
1015	.backlog_rcv =	ping_queue_rcv_skb,
1016	.release_cb =	ip4_datagram_release_cb,
1017	.hash =		ping_hash,
1018	.unhash =	ping_unhash,
1019	.get_port =	ping_get_port,
1020	.obj_size =	sizeof(struct inet_sock),
1021};
1022EXPORT_SYMBOL(ping_prot);
1023
1024#ifdef CONFIG_PROC_FS
1025
1026static struct sock *ping_get_first(struct seq_file *seq, int start)
1027{
1028	struct sock *sk;
1029	struct ping_iter_state *state = seq->private;
1030	struct net *net = seq_file_net(seq);
1031
1032	for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
1033	     ++state->bucket) {
1034		struct hlist_nulls_node *node;
1035		struct hlist_nulls_head *hslot;
1036
1037		hslot = &ping_table.hash[state->bucket];
1038
1039		if (hlist_nulls_empty(hslot))
1040			continue;
1041
1042		sk_nulls_for_each(sk, node, hslot) {
1043			if (net_eq(sock_net(sk), net) &&
1044			    sk->sk_family == state->family)
1045				goto found;
1046		}
1047	}
1048	sk = NULL;
1049found:
1050	return sk;
1051}
1052
1053static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
1054{
1055	struct ping_iter_state *state = seq->private;
1056	struct net *net = seq_file_net(seq);
1057
1058	do {
1059		sk = sk_nulls_next(sk);
1060	} while (sk && (!net_eq(sock_net(sk), net)));
1061
1062	if (!sk)
1063		return ping_get_first(seq, state->bucket + 1);
1064	return sk;
1065}
1066
1067static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
1068{
1069	struct sock *sk = ping_get_first(seq, 0);
1070
1071	if (sk)
1072		while (pos && (sk = ping_get_next(seq, sk)) != NULL)
1073			--pos;
1074	return pos ? NULL : sk;
1075}
1076
1077void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
1078	__acquires(ping_table.lock)
1079{
1080	struct ping_iter_state *state = seq->private;
1081	state->bucket = 0;
1082	state->family = family;
1083
1084	read_lock_bh(&ping_table.lock);
1085
1086	return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1087}
1088EXPORT_SYMBOL_GPL(ping_seq_start);
1089
1090static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
1091{
1092	return ping_seq_start(seq, pos, AF_INET);
1093}
1094
1095void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1096{
1097	struct sock *sk;
1098
1099	if (v == SEQ_START_TOKEN)
1100		sk = ping_get_idx(seq, 0);
1101	else
1102		sk = ping_get_next(seq, v);
1103
1104	++*pos;
1105	return sk;
1106}
1107EXPORT_SYMBOL_GPL(ping_seq_next);
1108
1109void ping_seq_stop(struct seq_file *seq, void *v)
1110	__releases(ping_table.lock)
1111{
1112	read_unlock_bh(&ping_table.lock);
1113}
1114EXPORT_SYMBOL_GPL(ping_seq_stop);
1115
1116static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
1117		int bucket)
1118{
1119	struct inet_sock *inet = inet_sk(sp);
1120	__be32 dest = inet->inet_daddr;
1121	__be32 src = inet->inet_rcv_saddr;
1122	__u16 destp = ntohs(inet->inet_dport);
1123	__u16 srcp = ntohs(inet->inet_sport);
1124
1125	seq_printf(f, "%5d: %08X:%04X %08X:%04X"
1126		" %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d",
1127		bucket, src, srcp, dest, destp, sp->sk_state,
1128		sk_wmem_alloc_get(sp),
1129		sk_rmem_alloc_get(sp),
1130		0, 0L, 0,
1131		from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
1132		0, sock_i_ino(sp),
1133		refcount_read(&sp->sk_refcnt), sp,
1134		atomic_read(&sp->sk_drops));
1135}
1136
1137static int ping_v4_seq_show(struct seq_file *seq, void *v)
1138{
1139	seq_setwidth(seq, 127);
1140	if (v == SEQ_START_TOKEN)
1141		seq_puts(seq, "  sl  local_address rem_address   st tx_queue "
1142			   "rx_queue tr tm->when retrnsmt   uid  timeout "
1143			   "inode ref pointer drops");
1144	else {
1145		struct ping_iter_state *state = seq->private;
1146
1147		ping_v4_format_sock(v, seq, state->bucket);
1148	}
1149	seq_pad(seq, '\n');
1150	return 0;
1151}
1152
 
 
 
 
 
 
 
1153static int ping_seq_open(struct inode *inode, struct file *file)
1154{
1155	struct ping_seq_afinfo *afinfo = PDE_DATA(inode);
1156	return seq_open_net(inode, file, &afinfo->seq_ops,
1157			   sizeof(struct ping_iter_state));
1158}
1159
1160const struct file_operations ping_seq_fops = {
1161	.open		= ping_seq_open,
1162	.read		= seq_read,
1163	.llseek		= seq_lseek,
1164	.release	= seq_release_net,
1165};
1166EXPORT_SYMBOL_GPL(ping_seq_fops);
1167
1168static struct ping_seq_afinfo ping_v4_seq_afinfo = {
1169	.name		= "icmp",
1170	.family		= AF_INET,
1171	.seq_fops	= &ping_seq_fops,
1172	.seq_ops	= {
1173		.start		= ping_v4_seq_start,
1174		.show		= ping_v4_seq_show,
1175		.next		= ping_seq_next,
1176		.stop		= ping_seq_stop,
1177	},
1178};
1179
1180int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
1181{
1182	struct proc_dir_entry *p;
1183	p = proc_create_data(afinfo->name, 0444, net->proc_net,
1184			     afinfo->seq_fops, afinfo);
1185	if (!p)
1186		return -ENOMEM;
1187	return 0;
1188}
1189EXPORT_SYMBOL_GPL(ping_proc_register);
1190
1191void ping_proc_unregister(struct net *net, struct ping_seq_afinfo *afinfo)
1192{
1193	remove_proc_entry(afinfo->name, net->proc_net);
1194}
1195EXPORT_SYMBOL_GPL(ping_proc_unregister);
1196
1197static int __net_init ping_v4_proc_init_net(struct net *net)
1198{
1199	return ping_proc_register(net, &ping_v4_seq_afinfo);
1200}
1201
1202static void __net_exit ping_v4_proc_exit_net(struct net *net)
1203{
1204	ping_proc_unregister(net, &ping_v4_seq_afinfo);
1205}
1206
1207static struct pernet_operations ping_v4_net_ops = {
1208	.init = ping_v4_proc_init_net,
1209	.exit = ping_v4_proc_exit_net,
1210};
1211
1212int __init ping_proc_init(void)
1213{
1214	return register_pernet_subsys(&ping_v4_net_ops);
1215}
1216
1217void ping_proc_exit(void)
1218{
1219	unregister_pernet_subsys(&ping_v4_net_ops);
1220}
1221
1222#endif
1223
1224void __init ping_init(void)
1225{
1226	int i;
1227
1228	for (i = 0; i < PING_HTABLE_SIZE; i++)
1229		INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
1230	rwlock_init(&ping_table.lock);
1231}
v3.15
   1/*
   2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
   3 *		operating system.  INET is implemented using the  BSD Socket
   4 *		interface as the means of communication with the user level.
   5 *
   6 *		"Ping" sockets
   7 *
   8 *		This program is free software; you can redistribute it and/or
   9 *		modify it under the terms of the GNU General Public License
  10 *		as published by the Free Software Foundation; either version
  11 *		2 of the License, or (at your option) any later version.
  12 *
  13 * Based on ipv4/udp.c code.
  14 *
  15 * Authors:	Vasiliy Kulikov / Openwall (for Linux 2.6),
  16 *		Pavel Kankovsky (for Linux 2.4.32)
  17 *
  18 * Pavel gave all rights to bugs to Vasiliy,
  19 * none of the bugs are Pavel's now.
  20 *
  21 */
  22
  23#include <linux/uaccess.h>
  24#include <linux/types.h>
  25#include <linux/fcntl.h>
  26#include <linux/socket.h>
  27#include <linux/sockios.h>
  28#include <linux/in.h>
  29#include <linux/errno.h>
  30#include <linux/timer.h>
  31#include <linux/mm.h>
  32#include <linux/inet.h>
  33#include <linux/netdevice.h>
  34#include <net/snmp.h>
  35#include <net/ip.h>
  36#include <net/icmp.h>
  37#include <net/protocol.h>
  38#include <linux/skbuff.h>
  39#include <linux/proc_fs.h>
  40#include <linux/export.h>
  41#include <net/sock.h>
  42#include <net/ping.h>
  43#include <net/udp.h>
  44#include <net/route.h>
  45#include <net/inet_common.h>
  46#include <net/checksum.h>
  47
  48#if IS_ENABLED(CONFIG_IPV6)
  49#include <linux/in6.h>
  50#include <linux/icmpv6.h>
  51#include <net/addrconf.h>
  52#include <net/ipv6.h>
  53#include <net/transp_v6.h>
  54#endif
  55
  56struct ping_table {
  57	struct hlist_nulls_head	hash[PING_HTABLE_SIZE];
  58	rwlock_t		lock;
  59};
  60
  61static struct ping_table ping_table;
  62struct pingv6_ops pingv6_ops;
  63EXPORT_SYMBOL_GPL(pingv6_ops);
  64
  65static u16 ping_port_rover;
  66
  67static inline int ping_hashfn(struct net *net, unsigned int num, unsigned int mask)
  68{
  69	int res = (num + net_hash_mix(net)) & mask;
  70
  71	pr_debug("hash(%d) = %d\n", num, res);
  72	return res;
  73}
  74EXPORT_SYMBOL_GPL(ping_hash);
  75
  76static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
  77					     struct net *net, unsigned int num)
  78{
  79	return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
  80}
  81
  82int ping_get_port(struct sock *sk, unsigned short ident)
  83{
  84	struct hlist_nulls_node *node;
  85	struct hlist_nulls_head *hlist;
  86	struct inet_sock *isk, *isk2;
  87	struct sock *sk2 = NULL;
  88
  89	isk = inet_sk(sk);
  90	write_lock_bh(&ping_table.lock);
  91	if (ident == 0) {
  92		u32 i;
  93		u16 result = ping_port_rover + 1;
  94
  95		for (i = 0; i < (1L << 16); i++, result++) {
  96			if (!result)
  97				result++; /* avoid zero */
  98			hlist = ping_hashslot(&ping_table, sock_net(sk),
  99					    result);
 100			ping_portaddr_for_each_entry(sk2, node, hlist) {
 101				isk2 = inet_sk(sk2);
 102
 103				if (isk2->inet_num == result)
 104					goto next_port;
 105			}
 106
 107			/* found */
 108			ping_port_rover = ident = result;
 109			break;
 110next_port:
 111			;
 112		}
 113		if (i >= (1L << 16))
 114			goto fail;
 115	} else {
 116		hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
 117		ping_portaddr_for_each_entry(sk2, node, hlist) {
 118			isk2 = inet_sk(sk2);
 119
 120			/* BUG? Why is this reuse and not reuseaddr? ping.c
 121			 * doesn't turn off SO_REUSEADDR, and it doesn't expect
 122			 * that other ping processes can steal its packets.
 123			 */
 124			if ((isk2->inet_num == ident) &&
 125			    (sk2 != sk) &&
 126			    (!sk2->sk_reuse || !sk->sk_reuse))
 127				goto fail;
 128		}
 129	}
 130
 131	pr_debug("found port/ident = %d\n", ident);
 132	isk->inet_num = ident;
 133	if (sk_unhashed(sk)) {
 134		pr_debug("was not hashed\n");
 135		sock_hold(sk);
 136		hlist_nulls_add_head(&sk->sk_nulls_node, hlist);
 137		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 138	}
 139	write_unlock_bh(&ping_table.lock);
 140	return 0;
 141
 142fail:
 143	write_unlock_bh(&ping_table.lock);
 144	return 1;
 145}
 146EXPORT_SYMBOL_GPL(ping_get_port);
 147
 148void ping_hash(struct sock *sk)
 149{
 150	pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
 151	BUG(); /* "Please do not press this button again." */
 
 
 152}
 153
 154void ping_unhash(struct sock *sk)
 155{
 156	struct inet_sock *isk = inet_sk(sk);
 
 157	pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
 
 158	if (sk_hashed(sk)) {
 159		write_lock_bh(&ping_table.lock);
 160		hlist_nulls_del(&sk->sk_nulls_node);
 
 161		sock_put(sk);
 162		isk->inet_num = 0;
 163		isk->inet_sport = 0;
 164		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 165		write_unlock_bh(&ping_table.lock);
 166	}
 
 167}
 168EXPORT_SYMBOL_GPL(ping_unhash);
 169
 170static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
 171{
 172	struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
 173	struct sock *sk = NULL;
 174	struct inet_sock *isk;
 175	struct hlist_nulls_node *hnode;
 176	int dif = skb->dev->ifindex;
 177
 178	if (skb->protocol == htons(ETH_P_IP)) {
 179		pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
 180			 (int)ident, &ip_hdr(skb)->daddr, dif);
 181#if IS_ENABLED(CONFIG_IPV6)
 182	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 183		pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n",
 184			 (int)ident, &ipv6_hdr(skb)->daddr, dif);
 185#endif
 186	}
 187
 188	read_lock_bh(&ping_table.lock);
 189
 190	ping_portaddr_for_each_entry(sk, hnode, hslot) {
 191		isk = inet_sk(sk);
 192
 193		pr_debug("iterate\n");
 194		if (isk->inet_num != ident)
 195			continue;
 196
 197		if (skb->protocol == htons(ETH_P_IP) &&
 198		    sk->sk_family == AF_INET) {
 199			pr_debug("found: %p: num=%d, daddr=%pI4, dif=%d\n", sk,
 200				 (int) isk->inet_num, &isk->inet_rcv_saddr,
 201				 sk->sk_bound_dev_if);
 202
 203			if (isk->inet_rcv_saddr &&
 204			    isk->inet_rcv_saddr != ip_hdr(skb)->daddr)
 205				continue;
 206#if IS_ENABLED(CONFIG_IPV6)
 207		} else if (skb->protocol == htons(ETH_P_IPV6) &&
 208			   sk->sk_family == AF_INET6) {
 209
 210			pr_debug("found: %p: num=%d, daddr=%pI6c, dif=%d\n", sk,
 211				 (int) isk->inet_num,
 212				 &sk->sk_v6_rcv_saddr,
 213				 sk->sk_bound_dev_if);
 214
 215			if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
 216			    !ipv6_addr_equal(&sk->sk_v6_rcv_saddr,
 217					     &ipv6_hdr(skb)->daddr))
 218				continue;
 219#endif
 
 
 220		}
 221
 222		if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)
 223			continue;
 224
 225		sock_hold(sk);
 226		goto exit;
 227	}
 228
 229	sk = NULL;
 230exit:
 231	read_unlock_bh(&ping_table.lock);
 232
 233	return sk;
 234}
 235
 236static void inet_get_ping_group_range_net(struct net *net, kgid_t *low,
 237					  kgid_t *high)
 238{
 239	kgid_t *data = net->ipv4.ping_group_range.range;
 240	unsigned int seq;
 241
 242	do {
 243		seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
 244
 245		*low = data[0];
 246		*high = data[1];
 247	} while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
 248}
 249
 250
 251int ping_init_sock(struct sock *sk)
 252{
 253	struct net *net = sock_net(sk);
 254	kgid_t group = current_egid();
 255	struct group_info *group_info;
 256	int i, j, count;
 257	kgid_t low, high;
 258	int ret = 0;
 259
 
 
 
 260	inet_get_ping_group_range_net(net, &low, &high);
 261	if (gid_lte(low, group) && gid_lte(group, high))
 262		return 0;
 263
 264	group_info = get_current_groups();
 265	count = group_info->ngroups;
 266	for (i = 0; i < group_info->nblocks; i++) {
 267		int cp_count = min_t(int, NGROUPS_PER_BLOCK, count);
 268		for (j = 0; j < cp_count; j++) {
 269			kgid_t gid = group_info->blocks[i][j];
 270			if (gid_lte(low, gid) && gid_lte(gid, high))
 271				goto out_release_group;
 272		}
 273
 274		count -= cp_count;
 
 275	}
 276
 277	ret = -EACCES;
 278
 279out_release_group:
 280	put_group_info(group_info);
 281	return ret;
 282}
 283EXPORT_SYMBOL_GPL(ping_init_sock);
 284
 285void ping_close(struct sock *sk, long timeout)
 286{
 287	pr_debug("ping_close(sk=%p,sk->num=%u)\n",
 288		 inet_sk(sk), inet_sk(sk)->inet_num);
 289	pr_debug("isk->refcnt = %d\n", sk->sk_refcnt.counter);
 290
 291	sk_common_release(sk);
 292}
 293EXPORT_SYMBOL_GPL(ping_close);
 294
 295/* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
 296static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk,
 297				struct sockaddr *uaddr, int addr_len) {
 298	struct net *net = sock_net(sk);
 299	if (sk->sk_family == AF_INET) {
 300		struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
 301		int chk_addr_ret;
 302
 303		if (addr_len < sizeof(*addr))
 304			return -EINVAL;
 305
 
 
 
 
 
 306		pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
 307			 sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
 308
 309		chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr);
 310
 311		if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
 312			chk_addr_ret = RTN_LOCAL;
 313
 314		if ((sysctl_ip_nonlocal_bind == 0 &&
 315		    isk->freebind == 0 && isk->transparent == 0 &&
 316		     chk_addr_ret != RTN_LOCAL) ||
 317		    chk_addr_ret == RTN_MULTICAST ||
 318		    chk_addr_ret == RTN_BROADCAST)
 319			return -EADDRNOTAVAIL;
 320
 321#if IS_ENABLED(CONFIG_IPV6)
 322	} else if (sk->sk_family == AF_INET6) {
 323		struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
 324		int addr_type, scoped, has_addr;
 325		struct net_device *dev = NULL;
 326
 327		if (addr_len < sizeof(*addr))
 328			return -EINVAL;
 329
 330		if (addr->sin6_family != AF_INET6)
 331			return -EINVAL;
 332
 333		pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
 334			 sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
 335
 336		addr_type = ipv6_addr_type(&addr->sin6_addr);
 337		scoped = __ipv6_addr_needs_scope_id(addr_type);
 338		if ((addr_type != IPV6_ADDR_ANY &&
 339		     !(addr_type & IPV6_ADDR_UNICAST)) ||
 340		    (scoped && !addr->sin6_scope_id))
 341			return -EINVAL;
 342
 343		rcu_read_lock();
 344		if (addr->sin6_scope_id) {
 345			dev = dev_get_by_index_rcu(net, addr->sin6_scope_id);
 346			if (!dev) {
 347				rcu_read_unlock();
 348				return -ENODEV;
 349			}
 350		}
 351		has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,
 352						    scoped);
 353		rcu_read_unlock();
 354
 355		if (!(isk->freebind || isk->transparent || has_addr ||
 
 356		      addr_type == IPV6_ADDR_ANY))
 357			return -EADDRNOTAVAIL;
 358
 359		if (scoped)
 360			sk->sk_bound_dev_if = addr->sin6_scope_id;
 361#endif
 362	} else {
 363		return -EAFNOSUPPORT;
 364	}
 365	return 0;
 366}
 367
 368static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr)
 369{
 370	if (saddr->sa_family == AF_INET) {
 371		struct inet_sock *isk = inet_sk(sk);
 372		struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
 373		isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
 374#if IS_ENABLED(CONFIG_IPV6)
 375	} else if (saddr->sa_family == AF_INET6) {
 376		struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
 377		struct ipv6_pinfo *np = inet6_sk(sk);
 378		sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr;
 379#endif
 380	}
 381}
 382
 383static void ping_clear_saddr(struct sock *sk, int dif)
 384{
 385	sk->sk_bound_dev_if = dif;
 386	if (sk->sk_family == AF_INET) {
 387		struct inet_sock *isk = inet_sk(sk);
 388		isk->inet_rcv_saddr = isk->inet_saddr = 0;
 389#if IS_ENABLED(CONFIG_IPV6)
 390	} else if (sk->sk_family == AF_INET6) {
 391		struct ipv6_pinfo *np = inet6_sk(sk);
 392		memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
 393		memset(&np->saddr, 0, sizeof(np->saddr));
 394#endif
 395	}
 396}
 397/*
 398 * We need our own bind because there are no privileged id's == local ports.
 399 * Moreover, we don't allow binding to multi- and broadcast addresses.
 400 */
 401
 402int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 403{
 404	struct inet_sock *isk = inet_sk(sk);
 405	unsigned short snum;
 406	int err;
 407	int dif = sk->sk_bound_dev_if;
 408
 409	err = ping_check_bind_addr(sk, isk, uaddr, addr_len);
 410	if (err)
 411		return err;
 412
 413	lock_sock(sk);
 414
 415	err = -EINVAL;
 416	if (isk->inet_num != 0)
 417		goto out;
 418
 419	err = -EADDRINUSE;
 420	ping_set_saddr(sk, uaddr);
 421	snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port);
 422	if (ping_get_port(sk, snum) != 0) {
 423		ping_clear_saddr(sk, dif);
 424		goto out;
 425	}
 426
 427	pr_debug("after bind(): num = %d, dif = %d\n",
 428		 (int)isk->inet_num,
 429		 (int)sk->sk_bound_dev_if);
 430
 431	err = 0;
 432	if (sk->sk_family == AF_INET && isk->inet_rcv_saddr)
 433		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 434#if IS_ENABLED(CONFIG_IPV6)
 435	if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr))
 436		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 437#endif
 438
 439	if (snum)
 440		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 441	isk->inet_sport = htons(isk->inet_num);
 442	isk->inet_daddr = 0;
 443	isk->inet_dport = 0;
 444
 445#if IS_ENABLED(CONFIG_IPV6)
 446	if (sk->sk_family == AF_INET6)
 447		memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
 448#endif
 449
 450	sk_dst_reset(sk);
 451out:
 452	release_sock(sk);
 453	pr_debug("ping_v4_bind -> %d\n", err);
 454	return err;
 455}
 456EXPORT_SYMBOL_GPL(ping_bind);
 457
 458/*
 459 * Is this a supported type of ICMP message?
 460 */
 461
 462static inline int ping_supported(int family, int type, int code)
 463{
 464	return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
 465	       (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0);
 466}
 467
 468/*
 469 * This routine is called by the ICMP module when it gets some
 470 * sort of error condition.
 471 */
 472
 473void ping_err(struct sk_buff *skb, int offset, u32 info)
 474{
 475	int family;
 476	struct icmphdr *icmph;
 477	struct inet_sock *inet_sock;
 478	int type;
 479	int code;
 480	struct net *net = dev_net(skb->dev);
 481	struct sock *sk;
 482	int harderr;
 483	int err;
 484
 485	if (skb->protocol == htons(ETH_P_IP)) {
 486		family = AF_INET;
 487		type = icmp_hdr(skb)->type;
 488		code = icmp_hdr(skb)->code;
 489		icmph = (struct icmphdr *)(skb->data + offset);
 490	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 491		family = AF_INET6;
 492		type = icmp6_hdr(skb)->icmp6_type;
 493		code = icmp6_hdr(skb)->icmp6_code;
 494		icmph = (struct icmphdr *) (skb->data + offset);
 495	} else {
 496		BUG();
 497	}
 498
 499	/* We assume the packet has already been checked by icmp_unreach */
 500
 501	if (!ping_supported(family, icmph->type, icmph->code))
 502		return;
 503
 504	pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n",
 505		 skb->protocol, type, code, ntohs(icmph->un.echo.id),
 506		 ntohs(icmph->un.echo.sequence));
 507
 508	sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
 509	if (sk == NULL) {
 510		pr_debug("no socket, dropping\n");
 511		return;	/* No socket for error */
 512	}
 513	pr_debug("err on socket %p\n", sk);
 514
 515	err = 0;
 516	harderr = 0;
 517	inet_sock = inet_sk(sk);
 518
 519	if (skb->protocol == htons(ETH_P_IP)) {
 520		switch (type) {
 521		default:
 522		case ICMP_TIME_EXCEEDED:
 523			err = EHOSTUNREACH;
 524			break;
 525		case ICMP_SOURCE_QUENCH:
 526			/* This is not a real error but ping wants to see it.
 527			 * Report it with some fake errno.
 528			 */
 529			err = EREMOTEIO;
 530			break;
 531		case ICMP_PARAMETERPROB:
 532			err = EPROTO;
 533			harderr = 1;
 534			break;
 535		case ICMP_DEST_UNREACH:
 536			if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
 537				ipv4_sk_update_pmtu(skb, sk, info);
 538				if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
 539					err = EMSGSIZE;
 540					harderr = 1;
 541					break;
 542				}
 543				goto out;
 544			}
 545			err = EHOSTUNREACH;
 546			if (code <= NR_ICMP_UNREACH) {
 547				harderr = icmp_err_convert[code].fatal;
 548				err = icmp_err_convert[code].errno;
 549			}
 550			break;
 551		case ICMP_REDIRECT:
 552			/* See ICMP_SOURCE_QUENCH */
 553			ipv4_sk_redirect(skb, sk);
 554			err = EREMOTEIO;
 555			break;
 556		}
 557#if IS_ENABLED(CONFIG_IPV6)
 558	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 559		harderr = pingv6_ops.icmpv6_err_convert(type, code, &err);
 560#endif
 561	}
 562
 563	/*
 564	 *      RFC1122: OK.  Passes ICMP errors back to application, as per
 565	 *	4.1.3.3.
 566	 */
 567	if ((family == AF_INET && !inet_sock->recverr) ||
 568	    (family == AF_INET6 && !inet6_sk(sk)->recverr)) {
 569		if (!harderr || sk->sk_state != TCP_ESTABLISHED)
 570			goto out;
 571	} else {
 572		if (family == AF_INET) {
 573			ip_icmp_error(sk, skb, err, 0 /* no remote port */,
 574				      info, (u8 *)icmph);
 575#if IS_ENABLED(CONFIG_IPV6)
 576		} else if (family == AF_INET6) {
 577			pingv6_ops.ipv6_icmp_error(sk, skb, err, 0,
 578						   info, (u8 *)icmph);
 579#endif
 580		}
 581	}
 582	sk->sk_err = err;
 583	sk->sk_error_report(sk);
 584out:
 585	sock_put(sk);
 586}
 587EXPORT_SYMBOL_GPL(ping_err);
 588
 589/*
 590 *	Copy and checksum an ICMP Echo packet from user space into a buffer
 591 *	starting from the payload.
 592 */
 593
 594int ping_getfrag(void *from, char *to,
 595		 int offset, int fraglen, int odd, struct sk_buff *skb)
 596{
 597	struct pingfakehdr *pfh = (struct pingfakehdr *)from;
 598
 599	if (offset == 0) {
 600		if (fraglen < sizeof(struct icmphdr))
 
 601			BUG();
 602		if (csum_partial_copy_fromiovecend(to + sizeof(struct icmphdr),
 603			    pfh->iov, 0, fraglen - sizeof(struct icmphdr),
 604			    &pfh->wcheck))
 605			return -EFAULT;
 606	} else if (offset < sizeof(struct icmphdr)) {
 607			BUG();
 608	} else {
 609		if (csum_partial_copy_fromiovecend
 610				(to, pfh->iov, offset - sizeof(struct icmphdr),
 611				 fraglen, &pfh->wcheck))
 612			return -EFAULT;
 613	}
 614
 615#if IS_ENABLED(CONFIG_IPV6)
 616	/* For IPv6, checksum each skb as we go along, as expected by
 617	 * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in
 618	 * wcheck, it will be finalized in ping_v4_push_pending_frames.
 619	 */
 620	if (pfh->family == AF_INET6) {
 621		skb->csum = pfh->wcheck;
 622		skb->ip_summed = CHECKSUM_NONE;
 623		pfh->wcheck = 0;
 624	}
 625#endif
 626
 627	return 0;
 628}
 629EXPORT_SYMBOL_GPL(ping_getfrag);
 630
 631static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
 632				       struct flowi4 *fl4)
 633{
 634	struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
 635
 
 
 636	pfh->wcheck = csum_partial((char *)&pfh->icmph,
 637		sizeof(struct icmphdr), pfh->wcheck);
 638	pfh->icmph.checksum = csum_fold(pfh->wcheck);
 639	memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
 640	skb->ip_summed = CHECKSUM_NONE;
 641	return ip_push_pending_frames(sk, fl4);
 642}
 643
 644int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
 645			void *user_icmph, size_t icmph_len) {
 646	u8 type, code;
 647
 648	if (len > 0xFFFF)
 649		return -EMSGSIZE;
 650
 
 
 
 
 651	/*
 652	 *	Check the flags.
 653	 */
 654
 655	/* Mirror BSD error message compatibility */
 656	if (msg->msg_flags & MSG_OOB)
 657		return -EOPNOTSUPP;
 658
 659	/*
 660	 *	Fetch the ICMP header provided by the userland.
 661	 *	iovec is modified! The ICMP header is consumed.
 662	 */
 663	if (memcpy_fromiovec(user_icmph, msg->msg_iov, icmph_len))
 664		return -EFAULT;
 665
 666	if (family == AF_INET) {
 667		type = ((struct icmphdr *) user_icmph)->type;
 668		code = ((struct icmphdr *) user_icmph)->code;
 669#if IS_ENABLED(CONFIG_IPV6)
 670	} else if (family == AF_INET6) {
 671		type = ((struct icmp6hdr *) user_icmph)->icmp6_type;
 672		code = ((struct icmp6hdr *) user_icmph)->icmp6_code;
 673#endif
 674	} else {
 675		BUG();
 676	}
 677
 678	if (!ping_supported(family, type, code))
 679		return -EINVAL;
 680
 681	return 0;
 682}
 683EXPORT_SYMBOL_GPL(ping_common_sendmsg);
 684
 685static int ping_v4_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 686			   size_t len)
 687{
 688	struct net *net = sock_net(sk);
 689	struct flowi4 fl4;
 690	struct inet_sock *inet = inet_sk(sk);
 691	struct ipcm_cookie ipc;
 692	struct icmphdr user_icmph;
 693	struct pingfakehdr pfh;
 694	struct rtable *rt = NULL;
 695	struct ip_options_data opt_copy;
 696	int free = 0;
 697	__be32 saddr, daddr, faddr;
 698	u8  tos;
 699	int err;
 700
 701	pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
 702
 703	err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph,
 704				  sizeof(user_icmph));
 705	if (err)
 706		return err;
 707
 708	/*
 709	 *	Get and verify the address.
 710	 */
 711
 712	if (msg->msg_name) {
 713		DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
 714		if (msg->msg_namelen < sizeof(*usin))
 715			return -EINVAL;
 716		if (usin->sin_family != AF_INET)
 717			return -EINVAL;
 718		daddr = usin->sin_addr.s_addr;
 719		/* no remote port */
 720	} else {
 721		if (sk->sk_state != TCP_ESTABLISHED)
 722			return -EDESTADDRREQ;
 723		daddr = inet->inet_daddr;
 724		/* no remote port */
 725	}
 726
 
 727	ipc.addr = inet->inet_saddr;
 728	ipc.opt = NULL;
 729	ipc.oif = sk->sk_bound_dev_if;
 730	ipc.tx_flags = 0;
 731	ipc.ttl = 0;
 732	ipc.tos = -1;
 733
 734	sock_tx_timestamp(sk, &ipc.tx_flags);
 735
 736	if (msg->msg_controllen) {
 737		err = ip_cmsg_send(sock_net(sk), msg, &ipc, false);
 738		if (err)
 
 739			return err;
 
 740		if (ipc.opt)
 741			free = 1;
 742	}
 743	if (!ipc.opt) {
 744		struct ip_options_rcu *inet_opt;
 745
 746		rcu_read_lock();
 747		inet_opt = rcu_dereference(inet->inet_opt);
 748		if (inet_opt) {
 749			memcpy(&opt_copy, inet_opt,
 750			       sizeof(*inet_opt) + inet_opt->opt.optlen);
 751			ipc.opt = &opt_copy.opt;
 752		}
 753		rcu_read_unlock();
 754	}
 755
 
 
 756	saddr = ipc.addr;
 757	ipc.addr = faddr = daddr;
 758
 759	if (ipc.opt && ipc.opt->opt.srr) {
 760		if (!daddr)
 761			return -EINVAL;
 
 
 762		faddr = ipc.opt->opt.faddr;
 763	}
 764	tos = get_rttos(&ipc, inet);
 765	if (sock_flag(sk, SOCK_LOCALROUTE) ||
 766	    (msg->msg_flags & MSG_DONTROUTE) ||
 767	    (ipc.opt && ipc.opt->opt.is_strictroute)) {
 768		tos |= RTO_ONLINK;
 769	}
 770
 771	if (ipv4_is_multicast(daddr)) {
 772		if (!ipc.oif)
 773			ipc.oif = inet->mc_index;
 774		if (!saddr)
 775			saddr = inet->mc_addr;
 776	} else if (!ipc.oif)
 777		ipc.oif = inet->uc_index;
 778
 779	flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
 780			   RT_SCOPE_UNIVERSE, sk->sk_protocol,
 781			   inet_sk_flowi_flags(sk), faddr, saddr, 0, 0);
 
 782
 783	security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
 784	rt = ip_route_output_flow(net, &fl4, sk);
 785	if (IS_ERR(rt)) {
 786		err = PTR_ERR(rt);
 787		rt = NULL;
 788		if (err == -ENETUNREACH)
 789			IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
 790		goto out;
 791	}
 792
 793	err = -EACCES;
 794	if ((rt->rt_flags & RTCF_BROADCAST) &&
 795	    !sock_flag(sk, SOCK_BROADCAST))
 796		goto out;
 797
 798	if (msg->msg_flags & MSG_CONFIRM)
 799		goto do_confirm;
 800back_from_confirm:
 801
 802	if (!ipc.addr)
 803		ipc.addr = fl4.daddr;
 804
 805	lock_sock(sk);
 806
 807	pfh.icmph.type = user_icmph.type; /* already checked */
 808	pfh.icmph.code = user_icmph.code; /* ditto */
 809	pfh.icmph.checksum = 0;
 810	pfh.icmph.un.echo.id = inet->inet_sport;
 811	pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
 812	pfh.iov = msg->msg_iov;
 813	pfh.wcheck = 0;
 814	pfh.family = AF_INET;
 815
 816	err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
 817			0, &ipc, &rt, msg->msg_flags);
 818	if (err)
 819		ip_flush_pending_frames(sk);
 820	else
 821		err = ping_v4_push_pending_frames(sk, &pfh, &fl4);
 822	release_sock(sk);
 823
 824out:
 825	ip_rt_put(rt);
 
 826	if (free)
 827		kfree(ipc.opt);
 828	if (!err) {
 829		icmp_out_count(sock_net(sk), user_icmph.type);
 830		return len;
 831	}
 832	return err;
 833
 834do_confirm:
 835	dst_confirm(&rt->dst);
 
 836	if (!(msg->msg_flags & MSG_PROBE) || len)
 837		goto back_from_confirm;
 838	err = 0;
 839	goto out;
 840}
 841
 842int ping_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 843		 size_t len, int noblock, int flags, int *addr_len)
 844{
 845	struct inet_sock *isk = inet_sk(sk);
 846	int family = sk->sk_family;
 847	struct sk_buff *skb;
 848	int copied, err;
 849
 850	pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
 851
 852	err = -EOPNOTSUPP;
 853	if (flags & MSG_OOB)
 854		goto out;
 855
 856	if (flags & MSG_ERRQUEUE) {
 857		if (family == AF_INET) {
 858			return ip_recv_error(sk, msg, len, addr_len);
 859#if IS_ENABLED(CONFIG_IPV6)
 860		} else if (family == AF_INET6) {
 861			return pingv6_ops.ipv6_recv_error(sk, msg, len,
 862							  addr_len);
 863#endif
 864		}
 865	}
 866
 867	skb = skb_recv_datagram(sk, flags, noblock, &err);
 868	if (!skb)
 869		goto out;
 870
 871	copied = skb->len;
 872	if (copied > len) {
 873		msg->msg_flags |= MSG_TRUNC;
 874		copied = len;
 875	}
 876
 877	/* Don't bother checking the checksum */
 878	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 879	if (err)
 880		goto done;
 881
 882	sock_recv_timestamp(msg, sk, skb);
 883
 884	/* Copy the address and add cmsg data. */
 885	if (family == AF_INET) {
 886		DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
 887
 888		if (sin) {
 889			sin->sin_family = AF_INET;
 890			sin->sin_port = 0 /* skb->h.uh->source */;
 891			sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
 892			memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 893			*addr_len = sizeof(*sin);
 894		}
 895
 896		if (isk->cmsg_flags)
 897			ip_cmsg_recv(msg, skb);
 898
 899#if IS_ENABLED(CONFIG_IPV6)
 900	} else if (family == AF_INET6) {
 901		struct ipv6_pinfo *np = inet6_sk(sk);
 902		struct ipv6hdr *ip6 = ipv6_hdr(skb);
 903		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
 904
 905		if (sin6) {
 906			sin6->sin6_family = AF_INET6;
 907			sin6->sin6_port = 0;
 908			sin6->sin6_addr = ip6->saddr;
 909			sin6->sin6_flowinfo = 0;
 910			if (np->sndflow)
 911				sin6->sin6_flowinfo = ip6_flowinfo(ip6);
 912			sin6->sin6_scope_id =
 913				ipv6_iface_scope_id(&sin6->sin6_addr,
 914						    IP6CB(skb)->iif);
 915			*addr_len = sizeof(*sin6);
 916		}
 917
 918		if (inet6_sk(sk)->rxopt.all)
 919			pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb);
 920		if (skb->protocol == htons(ETH_P_IPV6) &&
 921		    inet6_sk(sk)->rxopt.all)
 922			pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb);
 923		else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags)
 924			ip_cmsg_recv(msg, skb);
 925#endif
 926	} else {
 927		BUG();
 928	}
 929
 930	err = copied;
 931
 932done:
 933	skb_free_datagram(sk, skb);
 934out:
 935	pr_debug("ping_recvmsg -> %d\n", err);
 936	return err;
 937}
 938EXPORT_SYMBOL_GPL(ping_recvmsg);
 939
 940int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 941{
 942	pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
 943		 inet_sk(sk), inet_sk(sk)->inet_num, skb);
 944	if (sock_queue_rcv_skb(sk, skb) < 0) {
 945		kfree_skb(skb);
 946		pr_debug("ping_queue_rcv_skb -> failed\n");
 947		return -1;
 948	}
 949	return 0;
 950}
 951EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
 952
 953
 954/*
 955 *	All we need to do is get the socket.
 956 */
 957
 958void ping_rcv(struct sk_buff *skb)
 959{
 960	struct sock *sk;
 961	struct net *net = dev_net(skb->dev);
 962	struct icmphdr *icmph = icmp_hdr(skb);
 963
 964	/* We assume the packet has already been checked by icmp_rcv */
 965
 966	pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
 967		 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
 968
 969	/* Push ICMP header back */
 970	skb_push(skb, skb->data - (u8 *)icmph);
 971
 972	sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
 973	if (sk != NULL) {
 
 
 974		pr_debug("rcv on socket %p\n", sk);
 975		ping_queue_rcv_skb(sk, skb_get(skb));
 
 976		sock_put(sk);
 977		return;
 978	}
 979	pr_debug("no socket, dropping\n");
 980
 981	/* We're called from icmp_rcv(). kfree_skb() is done there. */
 982}
 983EXPORT_SYMBOL_GPL(ping_rcv);
 984
 985struct proto ping_prot = {
 986	.name =		"PING",
 987	.owner =	THIS_MODULE,
 988	.init =		ping_init_sock,
 989	.close =	ping_close,
 990	.connect =	ip4_datagram_connect,
 991	.disconnect =	udp_disconnect,
 992	.setsockopt =	ip_setsockopt,
 993	.getsockopt =	ip_getsockopt,
 994	.sendmsg =	ping_v4_sendmsg,
 995	.recvmsg =	ping_recvmsg,
 996	.bind =		ping_bind,
 997	.backlog_rcv =	ping_queue_rcv_skb,
 998	.release_cb =	ip4_datagram_release_cb,
 999	.hash =		ping_hash,
1000	.unhash =	ping_unhash,
1001	.get_port =	ping_get_port,
1002	.obj_size =	sizeof(struct inet_sock),
1003};
1004EXPORT_SYMBOL(ping_prot);
1005
1006#ifdef CONFIG_PROC_FS
1007
1008static struct sock *ping_get_first(struct seq_file *seq, int start)
1009{
1010	struct sock *sk;
1011	struct ping_iter_state *state = seq->private;
1012	struct net *net = seq_file_net(seq);
1013
1014	for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
1015	     ++state->bucket) {
1016		struct hlist_nulls_node *node;
1017		struct hlist_nulls_head *hslot;
1018
1019		hslot = &ping_table.hash[state->bucket];
1020
1021		if (hlist_nulls_empty(hslot))
1022			continue;
1023
1024		sk_nulls_for_each(sk, node, hslot) {
1025			if (net_eq(sock_net(sk), net) &&
1026			    sk->sk_family == state->family)
1027				goto found;
1028		}
1029	}
1030	sk = NULL;
1031found:
1032	return sk;
1033}
1034
1035static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
1036{
1037	struct ping_iter_state *state = seq->private;
1038	struct net *net = seq_file_net(seq);
1039
1040	do {
1041		sk = sk_nulls_next(sk);
1042	} while (sk && (!net_eq(sock_net(sk), net)));
1043
1044	if (!sk)
1045		return ping_get_first(seq, state->bucket + 1);
1046	return sk;
1047}
1048
1049static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
1050{
1051	struct sock *sk = ping_get_first(seq, 0);
1052
1053	if (sk)
1054		while (pos && (sk = ping_get_next(seq, sk)) != NULL)
1055			--pos;
1056	return pos ? NULL : sk;
1057}
1058
1059void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
 
1060{
1061	struct ping_iter_state *state = seq->private;
1062	state->bucket = 0;
1063	state->family = family;
1064
1065	read_lock_bh(&ping_table.lock);
1066
1067	return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1068}
1069EXPORT_SYMBOL_GPL(ping_seq_start);
1070
1071static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
1072{
1073	return ping_seq_start(seq, pos, AF_INET);
1074}
1075
1076void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1077{
1078	struct sock *sk;
1079
1080	if (v == SEQ_START_TOKEN)
1081		sk = ping_get_idx(seq, 0);
1082	else
1083		sk = ping_get_next(seq, v);
1084
1085	++*pos;
1086	return sk;
1087}
1088EXPORT_SYMBOL_GPL(ping_seq_next);
1089
1090void ping_seq_stop(struct seq_file *seq, void *v)
 
1091{
1092	read_unlock_bh(&ping_table.lock);
1093}
1094EXPORT_SYMBOL_GPL(ping_seq_stop);
1095
1096static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
1097		int bucket)
1098{
1099	struct inet_sock *inet = inet_sk(sp);
1100	__be32 dest = inet->inet_daddr;
1101	__be32 src = inet->inet_rcv_saddr;
1102	__u16 destp = ntohs(inet->inet_dport);
1103	__u16 srcp = ntohs(inet->inet_sport);
1104
1105	seq_printf(f, "%5d: %08X:%04X %08X:%04X"
1106		" %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d",
1107		bucket, src, srcp, dest, destp, sp->sk_state,
1108		sk_wmem_alloc_get(sp),
1109		sk_rmem_alloc_get(sp),
1110		0, 0L, 0,
1111		from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
1112		0, sock_i_ino(sp),
1113		atomic_read(&sp->sk_refcnt), sp,
1114		atomic_read(&sp->sk_drops));
1115}
1116
1117static int ping_v4_seq_show(struct seq_file *seq, void *v)
1118{
1119	seq_setwidth(seq, 127);
1120	if (v == SEQ_START_TOKEN)
1121		seq_puts(seq, "  sl  local_address rem_address   st tx_queue "
1122			   "rx_queue tr tm->when retrnsmt   uid  timeout "
1123			   "inode ref pointer drops");
1124	else {
1125		struct ping_iter_state *state = seq->private;
1126
1127		ping_v4_format_sock(v, seq, state->bucket);
1128	}
1129	seq_pad(seq, '\n');
1130	return 0;
1131}
1132
1133static const struct seq_operations ping_v4_seq_ops = {
1134	.show		= ping_v4_seq_show,
1135	.start		= ping_v4_seq_start,
1136	.next		= ping_seq_next,
1137	.stop		= ping_seq_stop,
1138};
1139
1140static int ping_seq_open(struct inode *inode, struct file *file)
1141{
1142	struct ping_seq_afinfo *afinfo = PDE_DATA(inode);
1143	return seq_open_net(inode, file, &afinfo->seq_ops,
1144			   sizeof(struct ping_iter_state));
1145}
1146
1147const struct file_operations ping_seq_fops = {
1148	.open		= ping_seq_open,
1149	.read		= seq_read,
1150	.llseek		= seq_lseek,
1151	.release	= seq_release_net,
1152};
1153EXPORT_SYMBOL_GPL(ping_seq_fops);
1154
1155static struct ping_seq_afinfo ping_v4_seq_afinfo = {
1156	.name		= "icmp",
1157	.family		= AF_INET,
1158	.seq_fops	= &ping_seq_fops,
1159	.seq_ops	= {
1160		.start		= ping_v4_seq_start,
1161		.show		= ping_v4_seq_show,
1162		.next		= ping_seq_next,
1163		.stop		= ping_seq_stop,
1164	},
1165};
1166
1167int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
1168{
1169	struct proc_dir_entry *p;
1170	p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net,
1171			     afinfo->seq_fops, afinfo);
1172	if (!p)
1173		return -ENOMEM;
1174	return 0;
1175}
1176EXPORT_SYMBOL_GPL(ping_proc_register);
1177
1178void ping_proc_unregister(struct net *net, struct ping_seq_afinfo *afinfo)
1179{
1180	remove_proc_entry(afinfo->name, net->proc_net);
1181}
1182EXPORT_SYMBOL_GPL(ping_proc_unregister);
1183
1184static int __net_init ping_v4_proc_init_net(struct net *net)
1185{
1186	return ping_proc_register(net, &ping_v4_seq_afinfo);
1187}
1188
1189static void __net_exit ping_v4_proc_exit_net(struct net *net)
1190{
1191	ping_proc_unregister(net, &ping_v4_seq_afinfo);
1192}
1193
1194static struct pernet_operations ping_v4_net_ops = {
1195	.init = ping_v4_proc_init_net,
1196	.exit = ping_v4_proc_exit_net,
1197};
1198
1199int __init ping_proc_init(void)
1200{
1201	return register_pernet_subsys(&ping_v4_net_ops);
1202}
1203
1204void ping_proc_exit(void)
1205{
1206	unregister_pernet_subsys(&ping_v4_net_ops);
1207}
1208
1209#endif
1210
1211void __init ping_init(void)
1212{
1213	int i;
1214
1215	for (i = 0; i < PING_HTABLE_SIZE; i++)
1216		INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
1217	rwlock_init(&ping_table.lock);
1218}